A popular game which variously is used for amusement, or in connection with advertising and promotion of a product or service, or as a game of chance, is a multiple-ply match the hidden indicia game. According to the generic concept of this game as conventionally available, the potential player is presented with a unit of game stock which is made of a lamination of at least two facially adhered webs of sheet material. The one face of the base web is printed with a visually ascertainable pattern of indicia, whether it be numbers, letters, other verbal symbols, non-verbal symbols, or series or combination of any of these. A face of the cover web also is printed with a visually ascertainable pattern of indicia, and the two webs are laminated together in such a way that the pattern of indicia on the one face of the base web is obscured. The potential player, upon coming into possession of a unit of the stock of such a game delaminates the two plies in order to ascertain whether the pattern of indicia provided on the cover ply bears a predetermined relationship to, e.g. is the same as, or complements or otherwise matches the pattern of indicia provided on the base ply.
In an ideal world where all game agents and players could be expected to be scrupulously honest, no means for guarding against fraudulent alteration of the game stock would be necessary. However, in the world which exists, it has been found to be advantageous if not essential to provide means for guarding against such fraudulent alteration, so that the theoretical number of winners, their distribution and the amount of prizes to be won will not exceed those which can be predicted from full knowledge of the game stock.
Drawbacks of priorly-existing concepts of stock for use in conducting and playing such games include that the stock cannot be printed with variable information using modern non-impact printing apparatus and techniques, and/or that lamination and/or delamination of the plies involves exposure of a pressure sensitive adhesive, which may foul printing or laminating apparatus, or may make premature discovery of the hidden indicia difficult to prevent and/or difficult to detect.